It won't, as there would be no additional contact area with the top hat on the inside because the O/D of the top hat flange is approximately the same as the inner spacer
and the hole in the speedo drive gearbox is also larger than the I/D of the top hat flange.
The purpose of the 06.7629 top hat spacer is to centre the larger (0.687") hole of the drive gearbox* as marshg246 says (also texasSlick in the link below) therefore, should be on the outside
of the drive gearbox as shown on the factory drawing and the one in Lineslinger's post.
I have assembled the wheel, all new parts, bearings in the proper place. I am using one Dons 1 piece axle. When I fit the speedometer drive to the wheel, there is a chaffing that I can hear. Its not terrible but I dont think there should be ANY contact with the Hub-Cover. I can see some...
www.accessnorton.com
*(The BG5330/171 drive gearbox is the same as used on the Triumph T140 etc. that has an axle that fits the hole).